One of three isomeric monoterpenes differing in the positions of their two double bonds (<greek>beta</greek>- and <greek>gamma</greek>-terpinene being the others). In <greek>alpha</greek>-terpinene th
e double bonds are at the 1- and 3-positions of the <ital>p</ital>-menthane skeleton. ChEBICHEBI:10334